Blowing device for rock drills



HIS A TTORNEY.

a m 79 mi n 5 m W n a 0 1 a w L av w 7 W 70 L. C. BAYLES BLOWING DEVICE FOR ROCK DRILLS Filed March 19, 1950 n immw 2 V I July 5, 1932.

Patented July 5, 1932 UNITED STATES LEWIS C. BAYLES; OF EASTON, PENNSYLVANIA, PANY, OF JERSEYQITY, NEW JERSEY, A

ASSIGNOR TO INGERSOLL-RAND COM- CORPORATION OF NEW JERSEY BLOWING nnvrcn FOR ROCK nRILLs' Application filed March 19, 1930. Serial No. 437,080.

This invention relates to rock drills, but more particularly to a blowing device for a fluid actuated rock drill of the hammer type.

One object of the invention is to provide a manually operated valve control which will permit the operator at will to suspend the operation of his drill and divert the full force of the pressure fluid through a hollow drill steel to the bottom of the drill hole for the purpose of blowing the accumulated cuttings from the hole. It is often found that the means ordinarily used for keeping the drill hole free from cuttings is inadequate and sufficient rock particles remain in the hole to bind the movement of the drill steel. Unless these cuttings are removed they may am the working implement to such an extent that it is impossible to continue drilling or even to remove it from the drill hole. In order to prevent such a condition it is desirable to have in the tool itself a supplementary means of clearing the hole. The most practicable method of cleaning the hole is to direct a stream of high pressure fluid to the bottom of the hole to blow it clean. The present invention permits the operator to perform this operation with very little effort and loss of time.

A further object of the invention is to give the operator the option of directing the exhaust of his tool either to the front or to the side. In practice it is frequently found that exhaust to the front is objectionable for the reason that in a dry drill the exhaust fluid stirs up a dust cloud and in a Wet drill, particularly in cold weather, the exhaust fluid frequently causes water to freeze near the drill hole making the-footing of the operator insecure and dangerous as well as adding greatly to his discomfort. Other objects are either obvious or will be pointed out hereinafter.

The invention consists of a valve held in its seat and operated manually by means of a spring handle. This valve is so located as to control the exhaust from the cylinder and also to control a port which leads to one side of a distributor valve. By shutting off the exhaust and by opening one side of the distributor valve to atmosphere simultaneously inder by any suitable means (not a passage 20 to the rear end of the held in position to malntam pressure on one side of the piston so that its reciprocation is arrested and pressure fluid forced into one end of the cylinder will find its way out through the hole in the hollow drill steel. The invention is more particularly illustrated in the accompanying drawing in which similar characters refer to similar parts.

igure 1 is a sectional elevation of a rock drill embodying the invention,

Figure 2 is a sectional View taken on the line 2-2 of Figure 1 looking in the direction indicated by the arrows in which the valve is shown in position" for normal operation with exhaust to the front Figure 3 is a the distributor valve is perspective view of the valve and handle from one end thereof,

Figure 4 is-a sectional view of the valve in the position for side exhaust, and

Figure 5 is a in position for blowing.

Referring to the drawing the invention is shown embodiedin a rock drill comprising a cylinder 10 having a piston chamber 11 in which reciprocates a piston 12. On the forward part of the piston 12 is a grooved extension 13 which passes through a front cylinder washer 14 and into fluted engagement with an internally grooved chuck 15. At the end of its forward stroke it strikes a working implement 17, in this instance a hollow drill steel. v

The washer 14 forms a closure for the front of the cylinder. The chuck 15 and the washer 14 areheld in position by means of a front head 16 which may be fastened to the cylshown).

The rear of the cylinder is closed by a valve seat'18 from which a passage '19 leads to the front end of the piston chamber and p sto chamber. r

Controlling these passages is a distributor valve 21 which in this instance is of the tapered disc type.

- Through the center of this valve is a rifle bar 22 which engages a rifle nut (not shown). A rotation mechanism 25 of standard construction in the head of the rifle bar imparts and to retaln a rotary movement to the drill steel in a well understood manner.

Surmounting the valve seat 18 1s a valve cover 24 having a chamber 23 to which pressure fluid may be admitted by any suitable means (not shown).

An annular groove of the piston chamber 27 opens therefrom.

An enlargement 28 of the cylinder 10 has a bore 29 which intersects the exhaust port 27. A passage 30 leads the enlargement into the bore 29. A cylindrical valve 37 having a head 36 at one end thereof is disposed in the bore 29.

A groove 31 cut transversely of the valve 37 is adapted to connect the exhaust port 27 and the passage 30. From a port 38 in the valve 37 divergent bores 32 lead to the ends of the valve. When the valve 37 is rotated so that the port 38 registers with the exhaust port 27 the exhaust is directed to the sides of the drill and when the valve is turned so that the groove 31 registers-with the exhaust port 27 the exhaust is directed-to the front of the tool through the passage 30 A passage 39 connects the bore 29 with a chamber 40 which is located in one of the seats of the distributor valve 21. During normal operation of the tool this passage is sealed by the valve 37 but when it is turned so that the exhaust port 27 is closed the port 38 registers with the passage 39 and opens the chamber 40 to atmosphere through the bore 32 thereby offsetting the pressure of fluid entrapped in the back end of the piston chamber by the backward motion of the piston and preventing the valve 21 from unseating.

The valve 37 is rotated by means of a spring handle 33 which consists of a coil of spring metal having two substantlally par- 26 is located centrally and an exhaust port allel arms or extensions 41 terminating 1n loops 42 having internal lugs 34. The loops 42 encircle the ends of the valve 37 and the lugs 34 engage in slots in the ends of the valve thereby providing means whereby the valve may be rotated. By encircling the ends of the valve the spring handle avoids obstructing the outlet ends of the bore 32.

The spring handle 33 also serves to hold the valve 37 tightly in the bore 29 as one arm 41 presses against the head 36 of the valve and the other exerts pressure against the side of the cylinder enlargement 28.

Depressions 43 in the side of the cylinder enlargement 28 serve to engage the lugs 34 the valve 37 against accidental rotation. I

In practice the operator places the valve 37 in either the position shown in Figure 1 or in Figure 4 and admits pressure fluid to the tool. Pressure fluid entering the valve chamber 23 passes around the end of the valve 21 through the passage 20 to the back end of from the front of the piston chamber forcing the piston 13 forward. When the piston 13 uncovers the exhaust port 27 the pressure fluid escapes to atmosphere, the pressure on the face of that part of the distributor valve 21 controlling the passage 20 is reduced and the valve rocks or oscillates closing the passage 20 and opening the passage 19.

This action is assisted by pressure built up by the compression of the fluid entrapped in the front end of the piston chamber by the forward motion of the piston which pressure is communicated through the passage 19 to the opposite face of the valve 21 thereby helping to open the passage19. When this passage is opened pressure fluid passes through it to the front end of the piston chamber and forces the piston backward. When the ex haust port is uncovered on the back stroke the same cycle of events occurs.

When the operator wishes to interrupt normal operation and blow the drill hole he moves the valve 37 to the position shown in Figure 5. Fluid pressure entering the passage 19 forces the piston 12 to the rear of the piston chamber. The valve 21 is prevented from oscillating by reason of the reduction of relative pressure on the face which controls the passage 20 because of the opening of the chamber to atmosphere through the passage 39 the port 38 and the bore 32. Pressure fluid in the front end of the piston chamber is forced forward along the grooves of the piston extension 13 through the chuck 15 and down the hollow drill steel 17 to the bottom of the drill hole whence it drives out the accumulated cuttings. When the hole is clear the operator restores the valve 37 to either of its operating positions and drilling is resumed.

I claim:

1. In a fluid actuated tool, the combination of a cylinder and a piston, inlet ports to each end of the cylinder, a fluid supply port, a distributor valve to connect the supply port with each inlet port alternately, a central exhaust port in the cylinder normally controlled by the piston, a vent port opening one side of the distributor valve to atmosphere, a movable valve in the cylinder con' trolling both the exhaust port and the vent port and havingaxial and transverse bores registrable with said ports. and adjustable to three positions in one of which the vent port is closed and the exhaust port opened to atmosphere at the side of the tool through the valve, in. the second of which the vent port is closed and the exhaust port opened to atmosphere at the front of the tool, and in the last of which the vent port is opened to atmosphere through the valve and the exhaust port is closed.

2. In a fluid actuated tool, the combination of a cylinder and a piston, inlet ports to each end of the cylinder, a fluid supply port, a distributor valve to connect the supply port with each inlet port alternately, a central exhaust port in the cylinder normally cont-rolled by the piston, a vent port opening one side of the distributor valve to atmosphere, a movable valve in the cylinder controlling the vent port and the exhaust port and having axial and transverse passages registrable therewith, said valve being adjustable to positions in which the vent port is closed and the exhaust is directed selectively to the front or the sides of the cylinder through said passages, or to a position in which the exhaust port is closed and the vent port opened to atmosphere.

3. In a fluid actuated tool, the combination of a cylinder and a piston, inlet ports to each end of the cylinder, a fluid supply port, a distributor valve to connect the supply port with each inlet port alternately, a central exhaust port in the cylinder normally controlled by the piston, a vent port opening one side of the distributor valve to atmosphere, a blower valve in the cylinder movable to control the vent port and the exhaust port, and a longitudinal passage in said blower valve opening at both ends and at a point intermediate of said ends, said intermediate opening eing registrable with the exhaust port to direct exhaust fluid through the blower valve transversely of the axis of the drill.

4. In a fluid actuated tool, the combination of a cylinder and a piston, inlet ports to each end of the cylinder, a fluid supply port, a distributor valve to connect the supply port with each inlet port alternately, a central exhaust port in the cylinder normally controlled by the piston, a vent port opening one side of the distributor valve to atmosphere, a blower valve in the cylinder movable to control the vent port and the exhaust port, a groove extending transversely of the axis of the blower valve adapted to register with the exhaust port to direct exhaust fluid towards the front of the drill,and a longitudinal passage in said blower valve opening at bothends and at a point intermediate of said ends, said intermediate opening being registrable with the exhaust port to direct exhaust fluid through the blower valve transversely of the axis of the drill.

5. In a fluid actuated tool, the combination of a cylinder and a piston, inlet ports to each end of the cylinder, a fluid supply port, a distributor valve to connect the supply port with each inlet port alternately, a central exhaust port in the cylinder normally controlled by the piston, a vent port opening one side of the distributor valve to atmosphere, a blower valve in the cylinder movable to control the vent port and the exhaust port, and a pair of longitudinal passages opening at each end of the blower valve and in the periphery thereof intermediate said ends, said intermediate opening being registrable with the sage in the blower valve opening at both ends thereof and at a point intermediate of said ends, said intermediate opening being registrable with the exhaust port to direct exhaust fluid through the blower valve transversely of the axis of the drill, and a handle for said blower valve having loops encircling the ends of the blower valve to permit free passage for the exhaust fluid through both ends of the valve.

In testimony whereof I have signed this specification.

LEWIS C. BAYLES. 

